Dictionary.com

trans-Neptunian object

or trans·nep·tu·ni·an ob·ject

[ trans-nep-too-nee-uhn ob-jikt, ‐jekt, ‐tyoo‐, tranz ]
/ ˈtræns nɛpˈtu ni ən ˈɒb dʒɪkt, ‐dʒɛkt, ‐ˈtyu‐, ˈtrænz /
Save This Word!

noun Astronomy.
any celestial object in our solar system whose orbit lies beyond Neptune, including Pluto: there may be some 70,000 trans-Neptunian objects orbiting 30–50 astronomical units from the sun, with diameters of at least 62 miles (100 km). Abbreviation: TNO
QUIZ
CUDDLE UP! A COZY QUIZ ON FALL WORDS HAS ARRIVED
If autumn is your ideal season, spice up your repertoire of "fall" vocabulary with this quiz on some warm and vivid descriptive words for the season.
Question 1 of 10
Which of the following words means “to make a crackling sound; crackle”?
Meet Grammar CoachWrite or paste your essay, email, or story into Grammar Coach and get grammar helpImprove Your Writing
Meet Grammar CoachImprove Your Writing
Write or paste your essay, email, or story into Grammar Coach and get grammar help

Origin of trans-Neptunian object

First recorded in 1920–25
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

How to use trans-Neptunian object in a sentence

Scientific definitions for trans-Neptunian object

trans-Neptunian object
[ trăns′nĕp-tōōnē-ən ]

A celestial object that orbits the sun at a greater distance on average than Neptune.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
FEEDBACK